Composite silicate materials

ABSTRACT

The present invention pertains to a crystalline hydrated layered sodium silicate/amorphous sodium silicate composite material with predetermined hardness ion sequestration properties achieved by control of the process for forming the material, and a process for making the material. The process for producing the crystalline hydrated layered sodium silicate/amorphous sodium silicate composite consists of producing a crystalline sodium disilicate by heating a sodium silicate at a specified time and temperature. The resulting material may include amorphous material, and the crystalline sodium disilicate can be either alpha-phase or delta-phase disilicate. This crystalline sodium disilicate is then hydrolyzed with up to 50.0 milliequivalents per gram of either H 3  O +  ions or OH -  ions. The resulting material can sequester Ca 2+  ions, Mg 2+  ions, or both, depending on the results desired, processing conditions, and starting materials used.

FIELD OF THE INVENTION

This invention relates to composite materials comprised of a crystallinehydrated layered alkali silicate and an amorphous alkali silicate thatexhibit the ability to reduce the activity of hardness ions in laundrywash water. In particular, this invention relates to crystallinehydrated layered alkali silicate/amorphous alkali silicate compositematerials useful as detergent ingredients.

BACKGROUND OF THE INVENTION

It is known that hard water ions, specifically calcium and magnesium,adversely affect the activity of soaps and detergents. These ionsdeactivate detergents and can form undesirable precipitates. Thus it isdesirable to remove these ions prior to reaction with the detergent. Oneway to do this is to soften the water prior to introduction into awashing machine. In many parts of the world, this is impractical orimpossible, but in most parts of the world it is expensive. Anotherapproach to remove hard water ions is by reaction with another materialin situ in the washer. Materials useful for removing hard water ionsinclude alkali silicates (non-crystalline silicates, crystallinesilicates and zeolites), particularly hydrated layered alkali silicates.

Hydrated layered silicates are materials chemically comprising SiO₂organized into layers (sheets) having a negative charge, with alkalications for charge compensation, and water located between these layers.Hydrated layered silicates have been known for a number of years, eithersynthetically produced or naturally occurring (McCulloch J. Am. Chem.Soc. 75, 2453 (1952)). The SiO₂ /Na₂ O ratios of these silicates rangefrom 4 to 20. The first synthetic hydrated layered silicate, having aSiO₂ /Na₂ O ratio of 4, was reported by Wills in 1953 (U.S. Pat. No.2,640,756). This synthetic hydrated layered silicate was claimed to beuseful as an ion exchange material, specifically for calcium. However,the structure of the synthetic hydrated layered silicate prepared byWills was not disclosed. In 1972, a naturally occurring tetrasilicate(SiO₂ /Na₂ O=4) was reported by Johan and Maglione (Johan and Maglione,Bull. Soc. Fr. Mineral. Crystallogr. 95, 371 (1972)). The structure ofthis material was identified as a hydrated layered silicate, and thename kanemite was given to this mineral. In The Chemistry of Silica 1979and J. Colloid Sci 19, 7, 648 (1964), Iler concluded from the results ofJohan and Maglione that the synthetic hydrated layered silicate claimedby Wills in 1953 was kanemite. Duplication of Wills' invention, asdemonstrated in an example herein, supports Iler's conclusions.Furthermore, Iler reported that crystalline hydrated layered alkalisilicates have the ability to ion exchange their sodium ions and protonswith other metal ions or organic ions. Iler's observations areconsistent with Wills' experimental findings on the calcium ion exchangeability of kanemite materials. The synthesis of kanemite has also beenreviewed by Beneke and Lagaly (Beneke and Lagaly, Amer. Mineral. 62, 763(1977)).

In recent years the use of crystalline layered silicates, especiallycrystalline disilicates, as detergent builders has been suggested (seeU.S. Pat. Nos. 4,585,642; 4,806,327; 4,950,310; 4,820,439; 4,664,839;and 4,959,170). These crystalline disilicates were synthesized andreported as early as 1966 (Williamson and Glasser, Physics and Chemistryof Glasses, Vol. 7, No. 4, August, 1966). While these patents claim thatcrystalline disilicates function when incorporated into detergents, thedisclosed crystalline layered silicates have not been accepted readilyby the worldwide detergent industry due to their poor ability to removehardness ions from wash water at temperatures below about 30° C.

Furthermore, there are circumstances where it may be necessary ordesirable to remove only one hardness ion or the other (Ca²⁺ or Mg²⁺).Some detergent formulations have been developed which worksynergistically with one hardness ion. Accordingly, it may beundesirable to remove that ion, or it may be desirable to reduce it to aparticular concentration to optimize detergent performance whileremoving the other ion. Finally, where only one ion is present in waterof a particular geographic region, it is only that ion (either calciumor magnesium) which can be removed from the wash water. In the past,tailoring builder materials to selectively sequester hardness ions wasdifficult or impossible.

It is an object of this invention to provide a composite materialcomprising a hydrated layered alkali silicate and an amorphous alkalisilicate that is more suitable as a detergent ingredient than previouslysuggested materials that it would replace. A further object of thisinvention is to provide a detergent composition that includes a hydratedlayered silicate/amorphous silicate composite that reduces the activityof hardness ions in the wash water without producing the detrimentalprecipitates of these ions produced by some other detergent additivesincluding sodium carbonate. It is a still further object of thisinvention to provide the chemistry and the processing necessary totailor the detergent builder and ion sequestering properties of thesehydrated layered silicate/amorphous silicate composite materials.

SUMMARY OF THE INVENTION

The present invention pertains to a crystalline hydrated layered sodiumsilicate/amorphous sodium silicate composite material with predeterminedhardness ion sequestration properties achieved by control of the processfor forming the material, and a process for making the material. Theprocess for producing the crystalline hydrated layered sodiumsilicate/amorphous sodium silicate composite consists of producing acrystalline sodium disilicate by heating a sodium silicate at aspecified time and temperature. The resulting material may includeamorphous material, and the crystalline sodium disilicate can be eitheralpha-phase or delta-phase disilicate. This crystalline sodiumdisilicate is then hydrolyzed with up to 50.0 milliequivalents of eitherH₃ O⁺ ions or OH⁻ ions per gram of anhydrous material. The resultingmaterial can sequester Ca²⁺ ions, Mg²⁺ ions, or both, depending on theresults desired.

DETAILED DESCRIPTION OF THE INVENTION

The crystalline hydrated layered alkali silicate/amorphous alkalisilicate composite products of this invention have superior detergentbuilding properties compared to their individual components, whichindicates the materials of the present invention are not a simplecombination of crystalline hydrated layered alkali silicate andamorphous alkali silicate. The crystalline hydrated layered alkalisilicate portion of the composite product belongs to a family ofmaterials also known as: hydrated layered silicates; hydrated sheet(alkali) silicates; crystalline (alkali) layered silicates; andcrystalline (alkali) silicates. The term "hydrated layered silicate"will be used herein to refer to the crystalline hydrated layered alkalisilicate portion of the composite of our invention.

The composite materials of the present invention are useful as detergentbuilders. As used herein, the term "builder" is intended to refer tomaterials which have the ability to remove hardness ions from solution.Detergent formulations generally comprise at a minimum, a surfactant (oremulsifier) and a builder. Such formulations may also include adjunctssuch as enzymes, brighteners, perfumes, bactericides, thickeners,stabilizers, citrates, phosphates, carbonates, polycarboxylates, andnitrilotriacetic acid (NTA), some of which also function as builders inthat they remove hardness ions from solution.

Hydrated layered silicates have the ability to sequester hardness ionsfrom solution. Amorphous alkali silicates are well known for theirability to sequester magnesium ions, to buffer, and to supply freealkalinity to the laundry wash water. The superior sequestrationproperties of the composite product prepared according to the process ofthis invention are believed to be due to the formation of a uniquestructure including a crystalline hydrated layered alkali silicate andan amorphous alkali silicate. The sequestration properties of thecomposite products can be tailored by altering the processes used toprepare the materials and thus the ultimate structure of the resultingmaterials.

Naturally occurring kanemite is a hydrated layered silicate with weaklybound water and an ability to bind hardness ions (as was shown in U.S.Pat. No. 2,640,756 and reported by Iler, J. Colloid Sci. 19, 7, 648(1964)). It is a tetrasilicate, and therefore has a SiO₂ /Na₂ O moleratio of 4, although this varies somewhat depending upon the history ofthe material. We have found that synthetic composites including kanemiteand amorphous sodium silicate have properties that distinguish them asdetergent builders from previously suggested layered silicates when usedalone. This has been achieved by controlling the chemistry and theprocessing of these hydrated layered silicate/amorphous silicatecomposites.

The products of this invention may be prepared by spray drying liquidsodium silicate having a solids content between 5 and 50 weight % toproduce a hydrous polysilicate having a 16 to 22% water content. Thespray dried product is then crystallized at temperatures of 600° to 800°C. for 15 minutes to 24 hours, depending on the process equipment andconditions. Finally, hydrated layered silicate/amorphous silicatecomposites of the present invention can be prepared by converting theresulting materials in an alkaline or acidic media followed by drying.The concentration of hydronium ions (i.e., H₃ O⁺) in the acidic media orhydroxyl ions (i.e., OH⁻) in the alkaline media employed will dictatethe final detergent builder properties of the resulting material.

Alternatively, amorphous sodium silicate glass may be used as a startingmaterial to produce the products of the present invention. The glass isground and mixed with water using about 80% glass and 20% water byweight. The mixture is then calcined at 600° to 800° F. for 15 to 24hours to form a crystalline mass. This can then be pulverized andtreated with an alkaline or acidic media as outlined above.

The composite materials of the present invention possess superiorproperties as compared with prior art detergent builder/sequesteringmaterials. These composite materials remain free flowing powders underambient or high humidity conditions. Under similar humidity conditions,prior art detergent builders such as crystalline disilicates become adilatent mass. In addition, the hydrated layered silicate compositematerials of this invention are more effective in reducing the activityof hardness ions in laundry wash water than previously reported kanemiteor crystalline disilicate materials. This is observed in a pH range of 8to 10, the operating pH range of most detergents currently in use. Thedetergent building properties of the hydrated layered silicate/amorphoussilicate composite materials of the present invention can be adjusted tomaximize performance in varying wash conditions. The inventors believesuch adaptability has not heretofore been known.

The exact SiO₂ /Na₂ O ratio of the hydrated layered silicate included inthe composite of the present invention depends on the history of thematerial and the extent of any hydrolysis that has taken place. TheX-ray diffraction pattern of the composite material indicates that itincludes hydrated layered silicate with the same crystalline structureas the mineral kanemite. Kanemite has a distinctive X-ray diffractionpattern summarized in Table 1 below. The data in Table 1 is summarizedfrom Joint Committee on Powder Diffraction Standards (JCPDS) File#25-1309. The mineral kanemite has been reported to have a SiO₂ /Na₂ Oratio of 4. However pure kanemite produced in accordance with theteachings of Beneke and nagaly (see above) was shown to have a SiO₂ /Na₂O ratio of only 3.36. This material gave an X-ray diffraction patternindicating pure kanemite which shows that the SiO₂ /Na₂ O ratio of purekanemite may be variable.

                  TABLE 1                                                         ______________________________________                                        X-ray Diffraction Pattern of Kanemite                                                d-spacing (A)                                                                          I/I.sub.o                                                     ______________________________________                                               10.3     100                                                                  5.13     50                                                                   4.01     100                                                                  3.64     50                                                                   3.44     90                                                                   3.16     70                                                                   3.09     70                                                                   2.480    80                                                                   2.386    60                                                                   2.073    40                                                                   1.995    50                                                                   1.929    40                                                                   1.464    40                                                                   1.191    40                                                            ______________________________________                                    

The composition of kanemite with a SiO₂ /Na₂ O ratio of 4 is 56.08%SiO₂, 14.49% Na₂ O, and 29.43% water on a weight basis. When heated to150° C., the weight lost due to water removal is approximately 16.82%.An additional 8.41% weight reduction occurs when water is driven off attemperatures between 150° C. and 280° C. The remaining 4.2% water can bedriven off at temperatures above 280° C. These dehydrated forms ofkanemite also have distinctive X-ray diffraction patterns which can befound in JCPDS Files #27-709 (NaHSi₂ O₅ --H₂ O) and #27-708 (NaHSi₂ O₅)which are incorporated herein by reference.

Synthetic kanemite (which will be referred to herein simply as"kanemite" since it possesses the same X-ray diffraction pattern asnatural kanemite) can be prepared by various methods including thehydrolysis of various species of crystalline sodium disilicates or thebase exchange of disilicic acids. Kanemite can also be recovered as thecrystallization product of sodium silicate solutions that have beenstored for long periods of time at ambient conditions or for shorterperiods of time at elevated temperatures. Seeding of the sodium silicatesolutions is advantageous if kanemite production is desirable.

Synthesis of the hydrated layered silicate/amorphous silicate compositesof the present invention can be accomplished by the following process:First, a solution of sodium silicate is prepared by dissolving sodiumsilicate glass in water. One standard method for making sodium silicateglass is by the fusion of a sodium source and a silica source attemperatures between 1100° C. to 1400° C. The SiO₂ /Na₂ O ratio of theamorphous glass can be controlled by varying the ratio of the sodiumsource and the silica source present during the fusion process. Theamorphous sodium silicate glass is then dissolved in soft water atambient conditions or at elevated temperatures and pressures to yieldliquid sodium silicate having a solids content between 5% and 50%. Theliquid silicate is then spray dried to produce a hydrous polysilicatehaving a 16 to 22% water content. Again, the ratio of the polysilicatewill depend on the initial sodium and silica sources used forproduction. The hydrous polysilicate is then crystallized by heating totemperatures of 600° C. to 800° C. for 15 minutes to 24 hours, dependingon the process equipment, the temperature, and whether the material isseeded. Finally, the crystallized products are slurried in an alkalineor acidic media followed by drying. Under these process conditions, onlycrystalline disilicate material will form. No other crystalline materialwill be produced.

The concentration of the ions (hydronium or hydroxyl) in the media willdictate the final detergent builder properties, including the SiO₂ /Na₂O ratio of the composite material. The composite material can either bedried by filtering the slurry and drying the filter cake at temperaturesup to 100° C. or by spray drying at temperatures up to 120° C.

The resulting composite material provides excellent builder behavior fordetergents. For example, the composite material does not cake whenexposed to atmospheric conditions. The material remains a free flowingpowder when exposed to 80% relative humidity for a period of at leastthree months. Ordinary crystalline disilicates become a dilatent masswithin a few weeks at such humidity. The buffering capacity of thecomposite material is excellent. Buffering takes place in an attractivepH range for effective laundering, i.e., a pH range of about 8 to 10.

The composite material of the present invention has a high ion bindingcapacity and will reduce the activity of both hardness water ions (Ca²⁺and Mg²⁺) in wash water if desired. This is superior to presently useddetergent builders such as Zeolite NaA and delta-phase disilicate.Zeolite NaA primarily exchanges calcium, and delta-phase disilicaterequires much higher pH ranges, generally 10 to 12, to provide effectivehardness ion binding capacity. Further, delta-phase disilicate maydissolve at these high pH conditions to produce undesirable precipitatesof calcium and magnesium silicates or hydroxides.

The hydrated layered silicate/amorphous silicate composite detergentbuilder of the present invention can be formulated into detergentformulations with most commonly used ingredients to form stablecompositions. Artionic, non-ionic and zwiterionic surfactants can beused in detergent formulations. Co-builders such as crystalline aluminosilicates including clays and zeolites such as Zeolite NaA, Zeolite MAP(maximum aluminum NaP phase), organic sequesterants and condensedpolyphosphates are also compatible with the material of the presentinvention, as are other conventional detergent ingredients. Spraydrying, agglomeration and dry blending methods can be utilized to formstable and efficient detergents containing the products of the presentinvention.

Further properties and advantages of the hydrated layeredsilicates/amorphous silicate composite compositions of the presentinvention are illustrated in the following examples.

EXAMPLES

The proportions are in parts by weight (pbw), percent weight (%), partsper million (ppm), moles or equivalents unless otherwise indicated. Thenotation, DI² -water, refers to double distilled water.

The calcium and magnesium ion exchange rates and capacities weredetermined for various products and are reported as the calcium exchangerate (CER), calcium exchange capacity (CEC), magnesium exchange rate(MgER), and magnesium exchange capacity (MgEC). The results shown in thetables are expressed as milligrams (mg) of CaCO₃ per gram (g) ofanhydrous product for both calcium and magnesium. For brevity, thecalcium and magnesium exchange capacities of the products of thisinvention, as described in the disclosure and recited in the claims, canalso be (and frequently are) expressed in units of milliequivalents ofCa (or Mg) per gram of anhydrous product.

The calcium and magnesium performance (CER, CEC, MgER, and MgEC) weredetermined as follows. The product (0.5 grams on an anhydrous basis) wasreacted with 250 milliliters (ml) of a solution containing eithercalcium or magnesium ions. The concentration of these solutions was 1000ppm expressed as CaCO₃. The stirred reaction mixture was buffered at apH of 10 with 2 to 3 ml of a solution of NH4Cl and NH₄ OH. Thetemperature was held at 25° C. (unless otherwise noted) during theexchange reaction. An aliquot (15 ml) was removed after 2 minutes todetermine the calcium and magnesium exchange rates (CER and MgER) bypulling the suspension through a 1.0 micron filter into a syringe. Asecond aliquot was removed at 15 minutes to determine the calcium andmagnesium exchange capacities (CEC and MgEC).

The filtrates from the calcium exchange reaction were analyzed forcalcium in solution as follows. A 5 ml aliquot of filtrate was combinedwith 5 ml of 1 molar NaOH and about 100 milligrams of hydroxy naphtholblue indicator. A titration to a definite blue end point was carried outwith 0.005 molar ethylene diaminotetracetic acid (EDTA), and the volumeof EDTA used was recorded.

A blank titration using 5 ml of the 1000 ppm CaCO₃ solution was carriedout using the same method and the volume of EDTA was recorded. Filtratesfrom the magnesium exchange reaction were analyzed in the same mannerexcept that 5 ml of an NH₄ OH/NH₄ Cl buffer and about 100 mg ofErichrome Black T(3-hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid monosodium salt, available from Sigma Chemical Co. of St. Louis,Mo.) were used.

The rates and capacities for calcium and magnesium ions removed by theproduct were calculated as mg of CaCO₃ /g of anhydrous product asfollows: ##EQU1## B=volume of EDTA for blank titration (ml) V=volume ofEDTA for sample titration (ml)

M=Molarity of EDTA solution

FW=Formula Weight of CaCO₃ (100.1 g/mole)

LOI=Loss on Ignition of product at 800° C. (%)

W=Weight of product (grams)

Phase identification of the examples was determined using standard X-raydiffraction techniques. A 5-50 two-theta scan was used.

Example 1

Delta-phase; SiO₂ /Na₂ O=2

Delta-phase sodium disilicate was prepared according to a processreported in the literature. A spray dried sodium silicate having 2 molesof SiO₂ for each mole of Na₂ O and 18% water was heated to 700° C. for 1hour. The crystalline mass was pulverized by ball milling. The productwas identified by X-ray diffraction as delta-phase sodium disilicate.

Example 2

Delta-phase and amorphous; SiO₂ /Na₂ O=2.4

A product including delta-phase sodium disilicate was prepared accordingto the following process. A spray dried sodium silicate having 2.4 molesof SiO₂ for each mole of Na₂ O and 18% water was heated to 700° C. for 1hour. The crystalline mass was pulverized by ball milling. The productwas identified as including a delta-phase sodium disilicate by X-raydiffraction.

Example 3

Delta-phase and amorphous; SiO₂ /Na₂ O=3.22

A product including delta-phase sodium disilicate was prepared accordingto the following process. A spray dried sodium silicate having 3.22moles of SiO₂ for each mole of Na₂ O and 18% water was heated to 700° C.for 1 hour. The crystalline mass was pulverized by ball milling. Theproduct was identified by X-ray diffraction as including a delta-phasesodium disilicate.

Example 4

Alpha-phase; SiO₂ /Na₂ O=2

Alpha-phase sodium disilicate was prepared according to the followingprocess. A spray dried sodium silicate having 2 moles of SiO₂ for eachmole of Na₂ O and 18% water was heated to 800° C. for 6 hours. Thecrystalline mass was pulverized by ball milling. The product wasidentified by X-ray diffraction as alpha-phase sodium disilicate.

Example 5

Delta-phase and amorphous; SiO₂ /Na₂ O=1.7

A product including delta-phase sodium disilicate was prepared accordingto the following process. A mixture comprised of 8 pbw of an amorphousground silicate glass having 1.7 moles of SiO₂ for each mole of Na₂ Oand 2 pbw of DI² -water was heated to 700° C. for 1 hour. Thecrystalline mass was pulverized by ball milling. The product wasidentified by X-ray diffraction as including a delta-phase sodiumdisilicate.

Example 6

Delta-phase and amorphous; SiO₂ /Na₂ O=1.5

A product including delta-phase sodium disilicate was prepared accordingto the following process. A mixture comprised of 8 pbw of an amorphousground silicate glass having 1.5 moles of SiO₂ for each mole of Na₂ Oand 2 pbw of DI² -water was heated to 700° C. for 1 hour. Thecrystalline mass was pulverized by ball milling. The product wasidentified by X-ray diffraction as including a delta-phase sodiumdisilicate.

Examples 7-16

Composite material of the present invention; SiO₂ /Na₂ O=2; ions: H₃ O⁺

A composite material was prepared according to the process of thepresent invention as follows. Twenty grams of crystalline delta-phasedisilicate from Example 1 was slurried in 300 milliliters of DI² -watercontaining various amounts of hydrochloric acid (HCl), as described inTable 2, for 2 minutes followed by filtering and drying at ambientconditions. The product was pulverized by ball milling. X-raydiffraction revealed that a kanemite phase was present.

As explained, the product is milled after both before and afterhydrolyzation. Although ball milling is specified, any appropriate typeof milling may be used. Preferably, such milling will reduce the averageparticle size of the product to less than 200 microns prior tohydrolyzation and to less than 75 microns after hydrolyzation. This willproduce material with sufficient surface area to allow diffusion of thehydrolyzing agent during hydrolysis, and sufficient surface area toprovide hardness ion removal upon introduction into wash water. If theparticles are too large before hydrolysis, only the outer particlelayers may be hydrolyzed resulting in partially hydrolyzed product withreduced effectiveness. Similarly, if the particles are too large afterhydrolysis, there may be insufficient surface area to allow effectivehardness ion removal, resulting in a need for higher doses of material,and increased cost.

Elemental analysis indicated that the SiO₂ /Na₂ O ratio of the productsdepended on the concentration of hydronium ions used during thehydrolysis step, as may be seen from Table 2. Hardness ion bindingperformance was observed to vary with the SiO₂ /Na₂ O ratio of theresulting product (which was a function of the H₃ O⁺ concentration), asobserved in Table 2.

                                      TABLE 2                                     __________________________________________________________________________    Hydrated Layered Silicates Synthesized by the Hydrolysis of Delta Phase       Product with a                                                                SiO.sub.2 /Na.sub.2 O of 2.0 from Example 1                                        Amount of                                                                            meq H.sub.3 O.sup.+ per gram of                                        product from                                                                         anhydrous product from                                            Example                                                                            Example 1                                                                            Example 1         LOI                                             No.  (grams)                                                                              (acid used was 2N HCl)                                                                    SiO.sub.2 /Na.sub.2 O                                                               %  CER                                                                              CEC                                                                              MgER                                                                              MgEC                               __________________________________________________________________________     7   20.0   0.00        2.20  13.98                                                                            228                                                                              259                                                                              253 335                                 8   20.0   0.24        2.35  15.72                                                                            249                                                                              272                                                                              273 345                                 9   20.0   0.60        2.45  22.60                                                                            238                                                                              291                                                                              331 370                                10   20.0   1.20        2.42  22.60                                                                            225                                                                              274                                                                              192 293                                11   20.0   2.40        2.74  31.07                                                                            241                                                                              294                                                                              225 324                                12   20.0   3.00        2.93  27.16                                                                            150                                                                              275                                                                              122 184                                13   20.0   3.60        3.13  27.70                                                                            166                                                                              284                                                                              110 164                                14   20.0   4.20        3.00  26.00                                                                            183                                                                              286                                                                              112 192                                15   20.0   4.80        3.25  23.68                                                                            197                                                                              292                                                                               30  95                                16   20.0   9.60        21.4  15.52                                                                             47                                                                               52                                                                               60  22                                __________________________________________________________________________

Examples 17-29

Composite material of the present invention; SiO₂ /Na₂ O=2.4; ions: H₃O⁺

A composite material was prepared according to the process of thepresent invention as follows. Twenty grams of material from Example 2was slurried in 300 milliliters of DI² -water containing various amountsof HCl, as described in Table 3 for 2 minutes followed by filtering anddrying at ambient conditions. The product was pulverized by ballmilling. X-ray diffraction revealed that a kanemite phase was present.

Elemental analysis indicated that the SiO₂ /Na₂ O ratio of the productsdepended on the concentration of hydronium ions used during thehydrolysis step, as may be seen from Table 3. Hardness ion bindingperformance was observed to vary with the SiO₂ /Na₂ O ratio of theresulting product (which was a function of the H₃ O⁺ concentration), asobserved in Table 3. Comparing Examples 17-29 to Examples 7-16, it canbe concluded that the hardness ion binding performance is dependent onboth the composition of the starting materials and the hydrolysisconditions under which the materials are processed.

                                      TABLE 3                                     __________________________________________________________________________    Hydrated Layered Silicates Synthesized by the Hydrolysis of Delta Phase       Product with a                                                                SiO.sub.2 /Na.sub.2 O of 2.4 from Example 2                                        Amount of                                                                            meq H.sub.3 O.sup.+ per gram of                                        product from                                                                         anhydrous product from                                            Example                                                                            Example 2                                                                            Example 2         LOI                                             No.  (grams)                                                                              (acid used was 2N HCl)                                                                    SiO.sub.2 /Na.sub.2 O                                                               %  CER                                                                              CEC                                                                              MgER                                                                              MgEC                               __________________________________________________________________________    17   20.0   0.00        3.94  25.60                                                                            206                                                                              271                                                                              63  163                                18   20.0   0.20        4.5   25.44                                                                            221                                                                              295                                                                              161 270                                19   20.0   0.40        4.49  25.73                                                                            197                                                                              282                                                                              172 292                                20   20.0   0.60        4.52  25.44                                                                            192                                                                              282                                                                              72  137                                21   20.0   0.80        4.62  25.51                                                                            161                                                                              270                                                                              62  142                                22   20.0   1.00        4.62  25.83                                                                            223                                                                              283                                                                              62  137                                23   20.0   1.50        4.72  25.8                                                                             208                                                                              284                                                                              78  143                                24   20.0   2.00        4.77  25.57                                                                            171                                                                              271                                                                              52  157                                25   20.0   3.00        4.92  24.95                                                                            201                                                                              280                                                                              37   82                                26   20.0   4.00        5.05  25.02                                                                            197                                                                              271                                                                              52  131                                27   20.0   5.00        5.39  24.22                                                                            159                                                                              239                                                                              48   93                                28   20.0   7.50        11.86 14.54                                                                             72                                                                               87                                                                              47   52                                29   20.0   10.00       125.45                                                                              12.42                                                                             27                                                                               27                                                                              12   17                                __________________________________________________________________________

Examples 30-42

Composite material of the present invention; SiO₂ /Na₂ O=3 22; ions: H₃O⁺

A composite material was prepared according to the process of thepresent invention as follows. Twenty grams of material from Example 3was slurried in 300 milliliters of DI² -water containing various amountsof HCl, as described in Table 4 for 2 minutes followed by filtering anddrying at ambient conditions. The product was pulverized by ballmilling. X-ray diffraction revealed that a kanemite phase was present.

Elemental analysis indicated that the SiO₂ /Na₂ O ratio of the productsdepended on the concentration of hydronium ions used during thehydrolysis step, as may be seen from Table 4. Hardness ion bindingperformance was observed to vary with the SiO₂ /Na₂ O ratio of the H₃ O⁺resulting product (which was a function of the 3 concentration), asobserved in Table 4. Comparing Examples 30-42 to Examples 7-29, it canbe concluded that the hardness ion binding performance is dependent onboth the composition of the starting materials and the hydrolysisconditions under which the materials are processed, since thesequestering rate and capacity differ in materials with very similar oridentical SiO₂ /Na₂ O ratios.

                                      TABLE 4                                     __________________________________________________________________________    Hydrated Layered Silicates Synthesized by the Hydrolysis of Delta Phase       Product with a                                                                SiO.sub.2 /Na.sub.2 O of 3.22 from Example 3                                       Amount of                                                                            meq H.sub.3 O.sup.+ per gram of                                        product from                                                                         anhydrous product from                                            Example                                                                            Example 3                                                                            Example 3         LOI                                             No.  (grams)                                                                              (acid used was 2N HCl)                                                                    SiO.sub.2 /Na.sub.2 O                                                               %  CER                                                                              CEC                                                                              MgER                                                                              MgEC                               __________________________________________________________________________    30   20.0   0.00        4.40  19.35                                                                            249                                                                              284                                                                              15  49                                 31   20.0   0.20        4.52  19.6                                                                             235                                                                              279                                                                              24  24                                 32   20.0   0.40        4.66  19.13                                                                            224                                                                              282                                                                              24  35                                 33   20.0   0.60        5.08  21.84                                                                            224                                                                              258                                                                              24  44                                 34   20.0   0.80        5.02  21.67                                                                            230                                                                              275                                                                              24  39                                 35   20.0   1.00        5.16  20.01                                                                            211                                                                              269                                                                              20  20                                 36   20.0   1.50        5.37  18.75                                                                            204                                                                              276                                                                               5  20                                 37   20.0   2.00        5.68  19.69                                                                            215                                                                              254                                                                              15  20                                 38   20.0   3.00        5.73  18.21                                                                            187                                                                              231                                                                              10  49                                 39   20.0   4.00        7.19  20.19                                                                            132                                                                              185                                                                              15  34                                 40   20.0   5.00        9.35  16.35                                                                             54                                                                              122                                                                              29  29                                 41   20.0   7.50        51.39 9.96                                                                              10                                                                               10                                                                               5   5                                 42   20.0   10.00       89.86 10.25                                                                             2  2  5   5                                 __________________________________________________________________________

Examples 43-52

Composite material of the present invention; SiO₂ /Na₂ O=2; ions: H₃ O⁺

A composite material was prepared according to the process of thepresent invention as follows. Twenty grams of crystalline alpha-phasedisilicate from Example 4 was slurried in 300 milliliters of DI² -watercontaining various amounts of HCl, as described in Table 5, for 2minutes followed by filtering and drying at ambient conditions. Theproduct was pulverized by ball milling. X-ray diffraction revealed thata kanemite phase was present.

Elemental analysis indicated that the SiO₂ /Na₂ O ratio of the hydratedlayered silicate composite products synthesized depended on theconcentration of hydronium ions used during the hydrolysis step.Hardness ion binding performance was observed to vary with the SiO₂ /Na₂O ratio of the hydrated layered silicate composite product, as observedin Table 5. It can be concluded from this series of examples and theprevious Examples 7-42 , and especially with Tables 2 and 3, that thehardness ion binding performance differs for the same SiO₂ /Na₂ O ratioproduct. Therefore, the hardness ion binding performance is dependentnot only on the composition, but also the crystalline phase of thestarting material and the hydrolysis conditions.

                                      TABLE 5                                     __________________________________________________________________________    Hydrated Layered Silicates Synthesized by the Hydrolysis of Alpha Phase       Product with a                                                                SiO.sub.2 /Na.sub.2 O of 2.0 from Example 4                                        Amount of                                                                            meq H.sub.3 O.sup.+ per gram of                                        product from                                                                         anhydrous product from                                            Example                                                                            Example 4                                                                            Example 4         LOI                                             No.  (grams)                                                                              (acid used was 2N HCl)                                                                    SiO.sub.2 /Na.sub.2 O                                                               %  CER                                                                              CEC                                                                              MgER                                                                              MgEC                               __________________________________________________________________________    43   20.0   0.00        3.69  14.57                                                                            53 108                                                                              120 235                                44   20.0   0.40        3.40  14.64                                                                            28  78                                                                              115 225                                45   20.0   0.80        3.63  17.12                                                                            48 103                                                                              100 205                                46   20.0   1.20        3.47  14.64                                                                            47  97                                                                               95 220                                47   20.0   1.60        3.74  15.34                                                                            47  87                                                                              100 190                                48   20.0   2.00        3.94  16.77                                                                            63 113                                                                               90 180                                49   20.0   2.50        4.09  19.81                                                                            88 148                                                                              135 205                                50   20.0   5.00        4.44  20.03                                                                            48 108                                                                               70 130                                51   20.0   7.50        5.41  18.52                                                                            38  73                                                                               45  60                                52   20.0   10.0        27.468                                                                              13.20                                                                            23  28                                                                               20  30                                __________________________________________________________________________

Examples 53-56

Composite material of the present invention; SiO₂ /Na₂ O=2; ions: OH⁻

A composite material was prepared according to the process of thepresent invention as follows. Twenty grams of crystalline delta-phasedisilicate from Example 1 was slurried in 300 milliliters of DI² -watercontaining various amounts of sodium hydroxide (NaOH) pellets, asdescribed in Table 6, for 2 minutes followed by filtering and drying atambient conditions. The product was pulverized by ball milling. X-raydiffraction revealed that a kanemite phase was present.

Elemental analysis indicated that the SiO₂ /Na₂ O ratio of the hydratedlayered silicate composite products synthesized depended on theconcentration of hydroxyl ions used during the hydrolysis step. Hardnession binding performance was observed to vary with the SiO₂ /Na₂ O ratioof the hydrated layered silicate composite product, as observed in Table6. It can be concluded from this example and the previous Examples 7-52,that the conversion of crystalline disilicates to composites withvariable and controllable sequestering properties can be accomplished ineither acidic or basic media.

                                      TABLE 6                                     __________________________________________________________________________    Hydrated Layered Silicates Synthesized by the Hydrolysis of Delta Phase       Product with a                                                                SiO.sub.2 /Na.sub.2 O of 2.0 from Example 1                                        Amount of                                                                            meq OH.sup.- per gram                                                  product from                                                                         anhydrous product from                                            Example                                                                            Example 1                                                                            Example 1 (base used                                                                            LOI                                             No.  (grams)                                                                              was NaOH pellets)                                                                         SiO.sub.2 /Na.sub.2 O                                                               %  CER                                                                              CEC                                                                              MgER                                                                              MgEC                               __________________________________________________________________________    53   20.0   1.0         3.24  26.72                                                                            265                                                                              325                                                                              251 303                                54   20.0   2.0         3.22  26.80                                                                            277                                                                              337                                                                              265 311                                55   20.0   20.0        2.91  24.86                                                                            240                                                                              294                                                                              243 298                                56   20.0   50.0        2.51  20.06                                                                            225                                                                              283                                                                              219 261                                __________________________________________________________________________

Examples 57-59

Composite material of the present invention; varying SiO₂ /Na₂ O; ions:H₃ O⁺ spray dried

Composite materials were prepared according to the process of thepresent invention as follows. Two hundred grams of material from each ofExamples 1, 3, and 6, were slurried in 1000 milliliters of DI² -watercontaining various amounts of HCl, as described in Table 7, for 15minutes. Each slurry was then introduced into a spray tower by either awheel atomizer or a nozzle atomizer using an inlet temperature of 150°to 300° C., an outlet temperature of 50° to 100° C., and a feed rate of10 to 75 cc/min, depending on the particular product processed. Productfrom the main chamber and cyclone chamber were combined. X-raydiffraction revealed that a kanemite phase was present in all cases.

Hardness ion binding performance and the SiO₂ /Na₂ O ratio of thehydrated layered silicate composite products can be found in Table 7. Itshould be noted that the SiO₂ /Na₂ O ratios of the resulting productsdid not change from the original SiO₂ /Na₂ O ratios since the materialwas spray dried. This is in contrast to previous examples where theproducts were crystallized and filtered resulting in the removal of somesoluble material in the supernatant liquid during the filtering step.

It can be concluded from this example and the above-mentioned examples,7 to 52, that the hardness ion binding performance is dependent on theprocessing of the hydrolyzed product. Specifically, comparing example 7to example 57, and example 30 to example 58, the SiO₂ /Na₂ O ratios ofthe resulting products are very similar, but the properties of thematerials differ. The magnesium ion binding capacity of the spray driedmaterials (examples 57 and 58) is much higher than the magnesium ionbinding capacity of the crystallized and filtered materials (examples 7and 30). However, the calcium ion binding capacity of the spray driedmaterials (examples 57 and 58) is much lower than the calcium ionbinding capacity of the crystallized and filtered materials (examples 7and 30). Thus the processing of the material dictates the properties ofthe resulting product.

                                      TABLE 7                                     __________________________________________________________________________    Hardness Ion Performance of Spray Dried Products                              __________________________________________________________________________         Feedstock                                                                            meq H.sub.3 O.sup.+  per gram                                          from   of anhydrous product                                              Example                                                                            Example                                                                              (acid used was    LOI                                             No.  No.    2N HCl)     SiO.sub.2 /Na.sub.2 O                                                               %  CER                                                                              CEC                                                                              MgER                                                                              MgEC                               __________________________________________________________________________    57   1      1.5         2.0   24.39                                                                            305                                                                              315                                                                              347 397                                58   3      0.5          3.22  9.13                                                                            225                                                                              280                                                                              242 283                                59   6      3.0         1.5   13.20                                                                            369                                                                              377                                                                              433 458                                __________________________________________________________________________

Example 60

Synthetic Pure Kanemite

Synthetic pure kanemite was prepared according to the literature (Benekeand Lagaly, Am. Miner. 62, 763 1977). One mole of SiO₂ was dispersed in100 milliliters of methanol. To this dispersion, a solution containingone mole of NaOH dissolved in 35 milliliters was slowly added to ensurethat the temperature of the sodium hydroxide/silica dispersion did notrise above room temperature. The resulting sodium hydroxide/silicaslurry was dried at 100° C. The dried mixture was heated to 700° C. for5.5 hours. The product was pulverized by ball milling. X-ray diffractionrevealed that delta-phase disilicate was present.

Twenty grams of this delta-phase disilicate product were slurried in 100milliliters of DI² -water for 5 minutes followed by filtering and airdrying at ambient conditions. The final product was pulverized by ballmilling. X-ray diffraction revealed that a pure kanemite phase waspresent.

Example 61

Hydrated Layered Tetrasilicate

A hydrated layered tetrasilicate was crystallized from a liquid silicatesolution having a composition of SiO₂ /Na₂ O of 3.22 and a solidscontent of 25% by heating to 100° C. for 5 days according to Wegst andWills (U.S. Pat. No. 2,179,806 and Re. U.S. Pat. No. 23,043). Theproduct was recovered from the solution by filtering and drying atambient conditions. X-ray diffraction revealed that a kanemite phase waspresent.

Comparison of the hardness ion binding performance for the product fromExample 60 to Examples 9, 57, and 61 indicates that the chemistry andprocessing history of these products are important factors, as seen inTable 8. In particular, the hardness ion binding performance of the purekanemite (shown in Example 60) is approximately 10% lower in calciumcapacity and approximately 35% lower in magnesium capacity when comparedto Example 9 and approximately 17% lower in calcium capacity andapproximately 40% lower in magnesium capacity when compared to example57.

                  TABLE 8                                                         ______________________________________                                        Comparison of Hardness Ion Binding Performance at 25° C.               of Hydrated Layered Silicate Products (from Examples 9 and                    57) to Previously Reported Kanemite Products (from                            Examples 60 and 61)                                                           Example SiO.sub.2 /Na.sub.2 O                                                 No.     Ratio      CER     CEC   MgER   MgEC                                  ______________________________________                                         9      2.45       238     291   331    370                                   57      2.0        305     315   347    397                                   60      3.36       200     260   120    240                                   61      4.29       140     210    65    115                                   ______________________________________                                    

Comparison of the hardness ion binding performance for this product toExample 9, 57 and 60 indicates that the chemistry and processing historyof these products are important factors, as seen in Table 8. Inparticular, the hardness ion binding performance of the hydrothermalcrystallized kanemite (Example 61) is approximately 28% lower in calciumcapacity and approximately 69% lower in magnesium capacity when comparedto example 9 and approximately 33% lower in calcium capacity andapproximately 71% lower in magnesium capacity when compared to example57.

The hardness ion binding performance for calcium and magnesium ofproducts produced in Examples 9, 57, 60 and 61 was determined as afunction of temperature. The results are summarized in Table 9. Theseresults indicate that hydrated layered silicate composite materials ofthis invention (Examples 9 and 57) have superior hardness ion bindingperformances compared to previously reported kanemite materials (i.e.Examples 60 and 61). Over the temperature range of 10° C. to 60° C., thehardness ion binding performance for the composite materials of thisinvention, Examples 9 and 57, are generally 15% and higher in calciumcapacity and 50% higher in magnesium capacity than kanemites preparedaccording to prior art references (Examples 60 and 61). It is especiallyimportant to note that the hydrated layered silicate/amorphous silicatecomposite materials of the present invention are very active at lowtemperatures which are encountered in today's laundering baths.

                  TABLE 9                                                         ______________________________________                                        Effect of Temperature on Hardness Ion Performance for                         Hydrated Layered Silicate versus Other Kanemite Materials                     Product from                                                                            Temperature                                                         Example No.                                                                             (°C.)                                                                             CER     CEC  MgER  MgEC                                  ______________________________________                                         9        10         225     275  265   340                                             25         238     291  331   370                                             60         300     305  450   470                                   57        10         285     290  225   250                                             25         305     315  347   397                                             60         315     325  380   405                                   60        10         145     240   30    45                                             25         200     260  120   240                                             60         245     285  160   275                                   61        10         --      --   --    --                                              25         140     210   65   115                                             60         --      --   --    --                                    ______________________________________                                    

The influence of pH on the hardness ion binding performance wasdetermined for the product from Example 9 by measuring the calcium andmagnesium binding performance at various pH values. The low pH valueswere maintained by adding an appropriate amount of HCl to the calciumand magnesium solutions. The higher pH values were maintained by addingan appropriate amount of NH₄ OH/NH₄ Cl buffer solution. The results aresummarized in Table 10. These results indicate that the product of thepresent invention has excellent hardness ion binding performance over arange of pH conditions. It should be noted that the hardness ion bindingperformance of the product of the present invention performs well in apH range common for detergent wash conditions.

                  TABLE 10                                                        ______________________________________                                        Effect of pH on Hardness Ion Binding                                          Performance at 25° C.                                                             Product from Example 57                                            pH           CEC       MgEC                                                   ______________________________________                                        8.5-9.0      252       255                                                    9.0-9.5      272       275                                                    9.5-10       282       305                                                    10           315       397                                                    ______________________________________                                    

The buffering capacities of products from Examples 9, 60 and 61 weremeasured by titration with 0.1 N HCl. The titrations were performed at25° C. on a Mettler DL-70 autotitrator. Sample weights were on a equalanhydrous weight basis, 0.2 grams, and the samples were slurried in 50ml of DI² -H₂ O. The results are summarized in Table 11. These resultsindicate that the product from Example 9 buffers more effectively in apH range of 8 to 10, a commonly used pH range in home laundering, thanthe products from examples 60 and 61.

                  TABLE 11                                                        ______________________________________                                        Buffering Capacity of Hydrated Layered Silicate Material                      and Other Kanemite Materials                                                  Volume of                                                                     0.1N HCl Product from                                                                              Product from                                                                              Product from                                 Added (ml)                                                                             Example 9 pH                                                                              Example 62 pH                                                                             Example 63 pH                                ______________________________________                                        0        11.235      10.293      10.068                                       3.428    10.302      9.098       6.802                                        5.142    9.968       8.853       6.175                                        6        9.832       8.778       5.463                                        6.5      9.759       8.600       4.810                                        7        9.685       8.325       3.659                                        7.5      9.606       8.264       --                                           8        9.531       7.899       --                                           9        9.379       7.191       --                                           10       9.220       6.420       --                                           11       9.088       5.733       --                                           12       8.982       5.076       --                                           13       8.859       4.161       --                                           14       8.770       --          --                                           15       8.500       --          --                                           16       7.880       --          --                                           ______________________________________                                    

The hardness ion binding performance was determined for mixtures of theproduct of the present invention (Example 9) and zeolite NaA at 25° C.The results are summarized in Table 12. These results show that theproducts of this invention are much more efficient ion exchangematerials for magnesium than zeolite NaA. These results also show that acombination of zeolite NaA with the products of the present inventionhave an attractive capacity for both hardness ions. For mixtures ofhydrated layered silicate/amorphous silicate composite and zeolite NaAcontaining 60-80% of the hydrated layered silicate composite, themagnesium capacity increased by 300% compared to pure zeolite NaA.

                  TABLE 12                                                        ______________________________________                                        Hardness Ion Performance for Mixtures of Hydrated                             Layered Silicate and Zeolite NaA                                              Product from                                                                             Zeolite NaA                                                        Example 9 (%)                                                                            (%)        CER    CEC  MgER  MgEC                                  ______________________________________                                         0         100        255    293   43    85                                   20         80         279    289  106   164                                   40         60         291    291  164   222                                   60         40         291    293  240   288                                   80         20         299    304  291   341                                   100         0         238    291  331   370                                   ______________________________________                                    

Stability of the hydrated layered silicate/amorphous silicate compositesof this invention to high humidity was determined by storing a physicalblend of 4 pbw composite material from example 9 and 6 pbw of acommercial detergent in a 80% relative humidity environment at roomtemperature for a period of 3 months. Stability of delta-phasedisilicate, an anhydrous crystalline material, was also determined atthe same physical blend proportions and relative humidity conditions.Stability is defined as the degree of clumping or caking of the blendthat occurs after storage at these conditions. After 3 months, thephysical blend of the product from Example 9 and the commercialdetergent remained a free flowing powder whereas the blend ofdelta-phase disilicate and the commercial detergent began to clump andcake after 2 weeks. The delta-phase disilicate/commercial detergentmixture eventually became a dilatent mass during the 3 month storageperiod.

Crystallinity of several of the hydrated layered silicate/amorphoussilicate composites of this invention were determined using standardanalytical X-ray diffraction methods. Example 60 was used as the X-raydiffraction standard and assigned a crystallinity value of 100%. Thepercent crystallinity was based on the peak areas under the following 8peak positions: 2.48 Å, 3.09 Å, 3.16 Å, 3.44 Å, 3.64 Å, 4.01 Å, 5.13 Å,and 10.3 Å. The results for various products of this invention are shownin Table 13. It is evident that the percent crystallinity, which is ameasure of the amount of kanemite present, depends on the processhistory of the sample.

                  TABLE 13                                                        ______________________________________                                        Crystallinity of Various Hydrated Layered                                     Silicate/Amorphous Silicate Composites                                                       Percent                                                        Example No.    Crystallinity                                                  ______________________________________                                        60 (Standard)  100%                                                            9             62%                                                            18             81%                                                            30             47%                                                            ______________________________________                                    

Examples 62-64

A hydrated layered silicate/amorphous silicate composite, according tothe process of the present invention, was prepared by slurrying 20 gramsof product from Example 1 in 300 ml of DI² water containing 0.6 meq ofhydronium ions per gram of anhydrous product, as described in Table 14,for 2 minutes, followed by filtering and drying at ambient conditions.The product was pulverized by ball milling. X-ray diffraction revealedthat a kanemite was present. Hardness ion binding performance wasindependent of the source of the hydronium ion.

                                      TABLE 14                                    __________________________________________________________________________    Hydrated Layered Silicates Synthesized by the Hydrolysis of Product from      Example 1 Using                                                               Different Sources of Hydronium Ions at Equivalent Hydronium Ion               Concentrations                                                                Example                                                                            Feedstock from                                                                        Mineral  Meq H.sub.3 O.sup.+  per gram                                                            LOI                                          No.  Example No.                                                                           Acid     of Anhydrous Product                                                                     (%)                                                                              CER                                                                              CEC                                                                              MgER                                                                              MgEC                            __________________________________________________________________________    62   1       Sulfuric Acid                                                                          0.6        23.8                                                                             225                                                                              285                                                                              311 349                                          (36N)                                                            63   1       Nitric Acid                                                                            0.6        20.1                                                                             230                                                                              277                                                                              324 355                                          (16N)                                                            64   1       Phosphoric Acid                                                                        0.6        22.9                                                                             220                                                                              275                                                                              305 345                                          (15N)                                                             9   1       Hydrochloric                                                                           0.6        22.6                                                                             238                                                                              291                                                                              331 370                                          Acid (2N)                                                        __________________________________________________________________________

What is claimed is:
 1. A process for producing a crystalline hydratedlayered sodium silicate/amorphous sodium silicate composite productcomprising:producing a material including a crystalline disilicate byheating a sodium silicate for a time, and at a temperature sufficient tocrystallize at least a portion of said material; and slurrying saidresulting solid material with a hydrolyzing agent providing up to 50.0milliequivalents of ions selected from H₃ O⁺ and OH⁻ ions per gram ofmaterial to hydrolyze said material.
 2. The process of claim 1 whereinsaid crystalline disilicate is delta-phase disilicate.
 3. The process ofclaim 1 wherein said crystalline disilicate is alpha-phase disilicate.4. The process of claim 2 wherein said ions are H₃ O⁺ ions.
 5. Theprocess of claim 2 wherein said ions are OH⁻ ions.
 6. The process ofclaim 4 wherein said hydrolyzing agent provides up to 5.0milliequivalents of H₃ O⁺ ions per gram of material and said sodiumsilicate has a SiO₂ :Na₂ O ratio of 2.0 prior to heating.
 7. The processof claim 4 wherein said hydrolyzing agent provides up to 5.0milliequivalents of H₃ O⁺ ions per gram of material and said sodiumsilicate has a SiO₂ :Na₂ O ratio of 2.4 prior to heating.
 8. The processof claim 4 wherein said hydrolyzing agent provides up to 5.0milliequivalents of H₃ O⁺ ions per gram of material and said sodiumsilicate has a SiO₂ :Na₂ O ratio of 3.22 prior to heating.
 9. Theprocess of claim 5 wherein said hydrolyzing agent provides up to 50milliequivalents of OH⁻ ions per gram of material and said sodiumsilicate has a SiO₂ :Na₂ O ratio of 2.0 prior to heating.
 10. Thecrystalline hydrated layered sodium silicate/amorphous sodium silicatecomposite product produced by the process of claim 6, wherein saidcomposite product has a SiO₂ /Na₂ O ratio between 2.2 and 3.3, and ahardness ion binding capacity of up to 5.9 milliequivalents Ca²⁺ pergram of anhydrous product and up to 7.4 milliequivalents Mg²⁺ per gramof anhydrous product.
 11. The crystalline hydrated layered sodiumsilicate/amorphous sodium silicate composite product produced by theprocess of claim 7, wherein said composite product has a SiO₂ /Na₂ Oratio between 3.9 and 5.4, and a hardness ion binding capacity of up to5.9 milliequivalents Ca²⁺ per gram of anhydrous product and up to 5.8milliequivalents Mg²⁺ per gram of anhydrous product.
 12. The crystallinehydrated layered sodium silicate/amorphous sodium silicate compositeproduct produced by the process of claim 8, wherein said compositeproduct has a SiO₂ /Na₂ O ratio between 4.4 and 9.4, and a hardness ionbinding capacity of up to 5.7 milliequivalents Ca²⁺ per gram ofanhydrous product and up to 1.0 milliequivalents Mg²⁺ per gram ofanhydrous product.
 13. The process of claim 3 wherein said hydrolyzingagent provides up to 5.0 milliequivalents of H₃ O⁺ ions per gram ofmaterial and said sodium silicate has a SiO₂ :Na₂ O ratio of 2.0 priorto heating.
 14. The crystalline hydrated layered sodiumsilicate/amorphous sodium silicate composite product produced by theprocess of claim 13, wherein said composite product has a SiO₂ /Na₂ Oratio between 3.4 and 4.5, and a hardness ion binding capacity of up to3.0 milliequivalents Ca²⁺ per gram of anhydrous product and up to 4.7milliequivalents Mg²⁺ per gram of anhydrous product.
 15. The process ofclaim 4 including, after hydrolyzing, the further step of spray dryingsaid hydrolyzed material.
 16. The process of claim 15 wherein saidhydrolyzing agent is calculated to provide up to 5.0 milliequivalents ofH₃ O⁺ ions per gram of material and said sodium silicate has a SiO₂ :Na₂O ratio of up to 3.22 prior to heating.
 17. The crystalline hydratedlayered sodium silicate/amorphous sodium silicate composite productproduced by the process of claim 16, wherein said composite product hasa SiO₂ /Na₂ O ratio up to 3.22, and a hardness ion binding capacity ofup to 7.6 milliequivalents Ca²⁺ per gram of anhydrous product and up to9.2 milliequivalents Mg²⁺ per gram of anhydrous product.
 18. Thecrystalline hydrated layered sodium silicate/amorphous sodium silicatecomposite product produced by the process of claim 9, wherein saidcomposite product has a SiO₂ /Na₂ O ratio between 2.50 and 3.25, and ahardness ion binding capacity of up to 6.75 milliequivalents Ca²⁺ pergram of anhydrous product and up to 6.25 milliequivalents Mg²⁺ per gramof anhydrous product.
 19. A process for producing a crystalline hydratedlayered sodium silicate/amorphous sodium silicate composite productcomprising:calcining an amorphous sodium silicate material having a SiO₂/Na₂ O ratio of 1.5 to 3.22 and a water content up to 95% by heating to600°-800° C. for up to 24 hours; milling said calcined material toproduce particles of less than 200 microns; hydrolyzing said solidcalcined material by slurrying said solid calcined material with anacidic or alkaline medium using 0 to 20 meq of H₃ O⁺ or OH⁻ per gram ofcalcined material; filtering and drying said hydrolyzed calcinedmaterial at a temperature up to 150° C.